Solidify Energy Claims 900-Mile EV Range with New Sulfide-Based Solid-State Battery

Munich, November 10, 2027 — Solidify Energy, a Munich-based battery startup founded in 2024, has published peer-reviewed data in Nature Energy demonstrating a sulfide-based solid-state battery cell with an energy density of 487 Wh/kg—a figure roughly 2.8 times higher than the best commercially available lithium-ion cells today.

The breakthrough centers on Solidify Energy's proprietary Sulf electrolyte, a lithium sulfide ceramic that remains conductive at room temperature and is compatible with high-voltage cathode materials that degrade conventional liquid electrolytes. The company paired the electrolyte with a lithium-metal anode (instead of graphite), enabling the dramatic density improvement.

In laboratory testing, a prototype cell roughly the size of a laptop battery achieved energy storage equivalent to a conventional 150 Wh/kg cell more than three times its physical volume. The cell also demonstrated 800 charge cycles with less than 8% capacity degradation—a key durability benchmark for automotive applications.

Critically, Solidify Energy says the battery supports 10-minute charging to 80% capacity using existing GB/T fast-charging infrastructure, removing one of the biggest practical barriers to solid-state adoption.

The company has secured a manufacturing partnership with a major Asian battery maker (name undisclosed) and plans to begin pilot production in 2029, targeting automotive OEM qualification by 2030. Solidify Energy has raised €620 million in total funding, its latest round led by Porsche Ventures and BP Ventures.

Toyota, QuantumScape, and Samsung SDI have all announced solid-state programs, but none have yet achieved the combination of energy density, cycle life, and room-temperature operation that Solidify Energy claims. Industry observers caution that scaling from laboratory cells to mass-producible automotive modules has derailed many previous battery breakthroughs.